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tof question of calculating mass of one atom

calc mass, in kg, of one atom of 49Ti. avagadro constant = 6.022x10^23.
for this I thought to just do the mr of Ti (49)/ 6.022x10^23. however the video I was watching said to calculate moles using n= no. of particles(1)/6.022x10^23 then input that answer into Mass= NxMr.
we got the same answer however he did it a long way and mine was short. can I keep doing it by just doing Mr/avagrado constant of do I have to find the moles first like he did?
Reply 1
Original post by sg.0
calc mass, in kg, of one atom of 49Ti. avagadro constant = 6.022x10^23.
for this I thought to just do the mr of Ti (49)/ 6.022x10^23. however the video I was watching said to calculate moles using n= no. of particles(1)/6.022x10^23 then input that answer into Mass= NxMr.
we got the same answer however he did it a long way and mine was short. can I keep doing it by just doing Mr/avagrado constant of do I have to find the moles first like he did?

Your method basically skips a few of the intermediate calculations in the moles method.

6.022 x 10^23 atoms in 1 mol, so 1 atom is 1 ÷ (6.022 x 1023)
mass = Mr x moles; = 49 x (1/(6.022 x 1023)) = 49/(6.022 x 1023) which is why your shorter method works :smile:

I think it's probably better to show that you understand the whole moles/mass link; you could probably get away with not calculating values in the intermediate steps (and leave them as fractions) but tbh markschemes can be a bit picky so it's generally best to show as much working as possible :smile:
Reply 2
oh okay thank you

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